In recent years, there has been growing interest in biopolymers. Biopolymers are found in living organisms and are naturally occurring polymers. Biopolymers originating from renewable resources are characterized by biodegradability. Biopolymers can be used in various applications, such as medicines, coatings, food, and packaging materials.
Polylactic acid (PLA), one of the most representative biodegradable resins, is highly transparent and has better heat resistance than other biodegradable resins. Polylactic acid can be mass-produced from vegetable raw materials such as corns and sweet potatoes, which is advantageous in terms of economic efficiency. Polylactic acid can contribute to the reduction of petroleum consumption, thus being considered a very useful polymer.
Conventional polymeric materials using petroleum resources as raw materials release carbon dioxide during incineration after use, resulting in an increase in atmospheric carbon dioxide concentration. In contrast, carbon dioxide emission from polylactic acid during incineration or biodegradation does not bring about an increase in atmospheric carbon dioxide concentration because the concentration of carbon dioxide emitted from polylactic acid is similar to atmospheric carbon dioxide levels.
Due to these advantages, polylactic acid is currently used in disposable products, garbage bags, etc. Polylactic acid is actively investigated for its applicability in various fields of daily life, including exterior materials of electronic products such as air cleaners and mobile phones, furniture such as chairs, and automotive components.
Acrylonitrile-butadiene-styrene (ABS) resins as thermoplastic polymers are used for the manufacture of lightweight products due to their low specific gravity. Other advantages of acrylonitrile-butadiene-styrene (ABS) resins are good molding processability, excellent mechanical properties such as high tensile strength and high impact strength, and superior thermal properties such as high coefficient of thermal expansion and high heat distortion temperature. Particularly, acrylonitrile-butadiene-styrene resins are mainly used as automotive materials and their consumption is steadily on the rise. Under such circumstances, efforts are needed to reduce costs associated with the disposal and incineration of waste acrylonitrile-butadiene-styrene resins.
For this purpose, research is actively underway to impart biodegradability to finished composites by the addition of small amounts of biodegradable resins such as polylactic acid to acrylonitrile-butadiene-styrene (ABS) resins.
However, there is a need to solve the problem of poor compatibility between polylactic acid and acrylonitrile-butadiene-styrene (ABS) resins, which is a cause of low impact strength of composites.